Back Bay Harry’s is a new restaurant in the space that was formerly Geoffrey’s. It’s named for partner Harry Collings; chef Jason Santos and designer Taniya Nayak are involved, too. Before he was the blue-haired guy on “Hell’s Kitchen,” Santos made his name at Gargoyles on the Square in Somerville; current local restaurants include Blue Inc. and Abby Lane. At Back Bay Harry’s, he offers a menu of creative comfort food: Chinese BBQ pork sliders, pastrami mac ’n’ cheese, fried chicken with honey doughnuts. The neighborhood is here -- coworkers, boyfriends and girlfriends, man dates, actual man dates, solo businessmen in search of a stiff drink. The place has black walls, pale wood floors, and big, arched windows that provide a view of Back Bay.